Getting error when I try to activate plugin

Fatal error: Uncaught Error: Class ‘digi\Digirisk’ not found in /home/vidhyape/public_html/wp-content/plugins/task-manager/core/action/task_manager.action.php:225 Stack trace: #0 /home/vidhyape/public_html/wp-includes/class-wp-hook.php(287): task_manager\Task_Manager_Action->callback_admin_menu(“) #1 /home/vidhyape/public_html/wp-includes/class-wp-hook.php(311): WP_Hook->apply_filters(NULL, Array) #2 /home/vidhyape/public_html/wp-includes/plugin.php(478): WP_Hook->do_action(Array) #3 /home/vidhyape/public_html/wp-admin/includes/menu.php(155): do_action(‘admin_menu’, “) #4 /home/vidhyape/public_html/wp-admin/menu.php(326): require_once(‘/home/vidhyape/…’) #5 /home/vidhyape/public_html/wp-admin/admin.php(153): require(‘/home/vidhyape/…’) #6 /home/vidhyape/public_html/wp-admin/plugins.php(10): require_once(‘/home/vidhyape/…) #7 (main) thrown in /home/vidhyape/public_html/wp-content/pluginsitask-manager/core/action/task_manager.action.php on line 225
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